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Spatial distribution and potential ecological and health risks associated with heavy metals in the Ijero-Ekiti mining site,Nigeria

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Regional Sustainability 2024年第1期5卷 26-41页

作者： johnson Adedeji OLUSOLA Adeyinka Oluyemi ATURAMU Olufunke ASAOLU Olusesan Sola OGUNLEYE Department of Geography and Planning Science Ekiti State UniversityAdo Ekiti360211Nigeria Institute of Ecology and Environmental Studies Obafemi Awolowo UniversityIle IfeOsun State220101Nigeria Department of Geology(Climate Change and Paleobiology Group) Ekiti State UniversityAdo Ekiti360211Nigeria Environmental Natural Resources and Blue EconomyEurope and Central AsiaWorld Bank GroupWashington D.C.20433the USA

Artisanal gold mining,a labor-intensive and antiquated technique,is a growing industry and the source of income for rural communities all over the ***,artisanal gold mining has potential negative and long-term effects on economy,environment,and *** study collected soil samples from 16 sample points including a control point to examine the pollution degrees and spatial distribution of heavy metals,as well as ecological and health risks associated with heavy metal pollution in the Ijero-Ekiti mining site,*** Information System(GIS)and remote sensing technologies were used to identify regions with high concentrations of heavy metals and assess the environmental impact of gold mining *** results show that the mean heavy metal concentrations of 16 soil pointa are 8.94(±5.97)mg/kg for As,0.18(±0.54)mg/kg for Cd,0.11(±1.06)mg/kg for Co,14.32(±3.43)mg/kg for Cr,6.89(±0.64)mg/kg for Cu,48.92(±11.77)mg/kg for Fe,135.81(±30.75)mg/kg for Mn,5.92(±0.96)mg/kg for Ni,5.72(±1.66)mg/kg for Pb,and 13.94(±1.38)mg/kg for *** study reveals that heavy metal concentration in soils follows the order of Mn>Fe>Cr>Zn>As>Cu>Ni>Pb>Co>*** analysis of soil samples indicates that 3 principal components(PCs)account for 70.008%of the total variance and there are strong positive correlations between various pairs of heavy *** total potential ecological risk index(309.599)in the study area is ***-carcinogenic risk suggests that there may be long-term health impacts on people who work in the mining areas due to chronic exposure to the *** on the study,the hazard index of carcinogenic health risks associated with heavy metals through ingestion is 520.00×10^(–4).Dermal contact from As and Cr also increases the risk of cancer,with the highest hazard index value of 18.40×10^(–4).The lowest exposure pathway,with the hazard index value of 0.68×10^(–4),indicates that the inhalation of heavy metals has a comparatively low risk of can

关键词： Artisanal gold mining Heavy metals Exposure pathway Potential ecological risk Geo-accumulation index Ijero-Ekiti mining site

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Pervasive Attentive Neural Network for Intelligent Image Classification Based on N-CDE’s

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Computers, Materials & Continua 2024年第4期79卷 1137-1156页

作者： Anas w.Abulfaraj Department of Information Systems Faculty of Computing and Information TechnologyKing Abdulaziz UniversityRabigh21911Saudi Arabia

The utilization of visual attention enhances the performance of image classification *** attentionbased models have demonstrated notable performance,but many of these models exhibit reduced accuracy when confronted with inter-class and intra-class similarities and ***-Controlled Differential Equations(N-CDE’s)and Neural Ordinary Differential Equations(NODE’s)are extensively utilized within this ***’s possesses the capacity to effectively illustrate both inter-class and intra-class similarities and differences with enhanced *** this end,an attentive neural network has been proposed to generate attention maps,which uses two different types of N-CDE’s,one for adopting hidden layers and the other to generate attention *** distinct attention techniques are implemented including time-wise attention,also referred to as bottom N-CDE’s;and element-wise attention,called topN-CDE’***,a trainingmethodology is proposed to guarantee that the training problem is sufficiently *** classification tasks including fine-grained visual classification andmulti-label classification,are utilized to evaluate the *** proposedmethodology is employed on five publicly available datasets,including CUB-200-2011,ImageNet-1k,PASCAL VOC 2007,PASCAL VOC 2012,and MS *** obtained visualizations have demonstrated that N-CDE’s are better appropriate for attention-based activities in comparison to conventional NODE’s.

关键词： Differential equations neural-controlled DE image classification attention maps N-CDE’s

One-pot and One-step Cu(0)-mediated Reversible-Deactivation Radical Polymerization of N-Isopropylacrylamide(NIPAM) in water

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Chinese Journal of Polymer Science 2024年第1期42卷 1-6,I0004页

作者： Zi-Shan Li Jing Lyu Bei Qiu Ying-Hao Li Ruth Foley Ri-Jian Song Melissa johnson Qiang Geng wen-Xin wang Institute of Precision Medicine(AUST-IPM) Anhui University of Science and TechnologyHuainan 232001China Charles Institute of Dermatology School of MedicineUniversity College DublinDublin D04 V1W8Ireland

Copper(0)-mediated reversible-deactivation radical polymerization(Cu(0)-mediated RDRP) of the water-soluble monomer Nisopropylacrylamide(NIPAM) has been challenging with the problems of high dispersity, poor control over the molecular weights(Mws) or complex or multi reaction steps, etc. In this work, we report the well-controlled polymerization of NIPAM in water via a facile one-pot and one-step Cu(0)-mediated RDRP. The results of this approach show that the key for kicking off the Cu(0)-mediated NIPAM RDRPs is to ensure sufficient Cu~I at the very beginning, and the key to achieve a well-controlled chain growth is to provide adequate deactivation strength during the polymerization process. For NIPAM, which has a high propagation rate constant, the deactivation control can be effectively enhanced by extra adding deactivator(i.e., Cu~II) to the system. Moreover, a low reaction temperature(4 ℃) is necessary in the controlled synthesis of higher Mw poly(Nisopropylacrylamide)(PNIPAM) to avoid the compromise in control caused by the phase transition from its lower critical solution temperature(LCST). Through this new kinetically controlled strategy, PNIPAMs with well-defined structure, narrow molecular weight distributions(MwDs) and varied Mws were successfully achieved.

关键词： Cu(0)-mediated RDRP N-isopropylacrylamide Propagation Deactivation Reaction parameters

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The quasi-Gramian solution of a non-commutative extension of the higher-order nonlinear Schr?dinger equation

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Communications in Theoretical Physics 2024年第3期76卷 51-61页

作者： H w A Riaz J Lin Department of Physics Zhejiang Normal UniversityJinhua 321004China

The nonlinear Schr?dinger(NLS)equation,which incorporates higher-order dispersive terms,is widely employed in the theoretical analysis of various physical *** this study,we explore the non-commutative extension of the higher-order NLS *** treat real or complex-valued functions,such as g_(1)=g_(1)(x,t)and g_(2)=g_(2)(x,t)as non-commutative,and employ the Lax pair associated with the evolution equation,as in the commutation *** derive the quasi-Gramian solution of the system by employing a binary Darboux *** soliton solutions are presented explicitly within the framework of *** visually understand the dynamics and solutions in the given example,we also provide simulations illustrating the associated ***,the solution can be used to study the stability of plane waves and to understand the generation of periodic patterns within the context of modulational instability.

关键词： integrable systems Darboux transformation solitons

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Efficient guiding and focusing of intense laser pulse using periodic thin slits

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Matter and Radiation at Extremes 2024年第4期9卷 29-39页

作者： L.Xu T.w.Huang k.Jiang C.N.wu H.Peng P.C.hen R.Li H.B.Zhuo C.T.Zhou Shenzhen key Laboratory of Ultraintense Laser and Advanced Material Technology Center for Intense Laser ApplicationTechnologyand College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118People’s Republic of China

Slits have been widely used in laser-plasma interactions as plasma optical components for generating high-harmonic light and controlling laser-driven particle ***,we propose and demonstrate that periodic thin slits can be regarded as a new breed of optical elements for efficient focusing and guiding of intense laser *** fundamental physics of intense laser interaction with thin slits is studied,and it is revealed that relativistic effects can lead to enhanced laser focusing far beyond the pure diffractive focusing *** addition,the interaction of an intense laser pulse with periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energy transfer efficiency compared with conventional *** results provide a novel method for manipulating ultra-intense laser pulses and should be of interest for many laser-based applications.

关键词： laser pulse intense

Recent Advances in the Synthesis and Polymerization of New CO_(2)-Based Cyclic

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Chinese Journal of Chemistry 2024年第4期42卷 430-443页

作者： Matteo Lanzi Arjan w.kleij Institute of Chemical Research of Catalonia(ICIQ) The Barcelona Institute of Science and Technology(BIST)Av.Països Catalans 1643007 TarragonaSpain Catalan Institute of Research and Advanced Studies(ICREA) Pg.Lluís Companys 2308010 BarcelonaSpain

Carbon dioxide can be converted into functional heterocycles known as cyclic carbonates,whose recent reactivity has been expanded towards the formation of tailor-made engineering *** minireview gives an overview of the most topical developments in this area with a special focus on the synthetic methods employed to prepare these CO_(2)based *** addition,their application potential in the area of polymer science using a variety of polymerization techniques is discussed that have in common the ring-opening of the carbonate *** perspectives are provided that provide impetus for the scientific communities aligning research to the use of sustainable processes for polymers from recyclable carbon sources such as CO_(2).

关键词： Carbon dioxide Cyclic carbonates Functional macromolecules Heterocycles Polycarbonates Recycling Ring opening polymerization

Exploring the effects of coronary artery disease as a preexisting comorbidity on mortality in hospitalized septic patients:a retrospective observation study

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Emergency and Critical Care Medicine 2024年第2期4卷 47-51页

作者： Anmol Multani Greg Stahl kerry johnson Scott Goade Robert D.Arnce College of Osteopathic Medicine Kansas City UniversityJoplinMOUSA Department of Data Improvement Freeman Health SystemJoplinMOUSA Department of Mathematics Missouri Southern State UniversityJoplinMOUSA Department of Pharmacy Freeman Health SystemJoplinMOUSA

Background:Sepsis has high prevalence and mortality rate,and it is imperative to identify populations at risk of poor sepsis *** patients with preexisting chronic comorbidities are shown to have worse sepsis *** identifying comorbidities with greater influence on sepsis progression,we can direct limited resources to septic patients with comorbidities and reduce health care *** comorbidities can impact the risk of developing sepsis and having worse *** artery disease(CAD)is a common comorbidity,especially in the elderly,and a leading cause of death *** wished to investigate the influence of CAD as a comorbidity on sepsis and hypothesized that preexisting CAD would increase mortality in hospitalized septic ***:we conducted retrospective observational study using patient data from Freeman Health System in Joplin,*** analyzed patient records from Freeman Health System database from January 1,2019,to June 30,*** patients were identified using the International Classification of Diseases,Tenth Revision sepsis *** identify septic patients with preexisting CAD,we used International Classification of Diseases,Tenth Revision codes for *** compared mortality rates for septic patients with and without ***:Two-sample proportion test was conducted to test the difference in mortality between septic patients with and without preexisting *** difference in mortality for the total population was−0.016(P=0.553).In the male and female subgroups,the differences in mortality were 0.0122(P=0.739)and−0.0511(P=0.208),*** differences in mortality in patients aged 40 to 64 years and 65 years and older were−0.0077(P=0.870)and 0.0007(P=0.983),*** statistical tests failed to find significant differences when comparing septic patients with and without preexisting *** was no significant difference in the age and sex ***:Our study showed that CAD alone was n

关键词： Comorbidity Coronary artery disease Inflammation Mortality rate in sepsis prognosis Sepsis

Effect of Eu3+,Bi3+,and Li+ doping on luminescent property of GdNbO4

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Journal of Rare Earths 2024年第1期42卷 66-75页

作者： S.w.wi Y.S.Lee Department of Physics and Integrative Institute of Basic Sciences Soongsil University

we investigated the emission properties of Eu3+-doped GdNbO4-based oxide phosphors,aiming at improving the Eu3+emission by codoping of Bi3+and Li+.Eu3+singly doped,Eu3+and Bi3+doubly doped,and Eu3+,Bi3+,and Li+triply doped GdNbO4were prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu3+in the singly doped samples are significantly improved by the codoping of Bi3+,mainly due to the energy transfer from Bi3+to Eu3+.The additional codoping of Li+is found to increase the Eu3+emission *** improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu3+in GdNbO4does not change significantly with the codoping of Bi3+and Li+.Our results indicate that Li+doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO4phosphors.

关键词： Eu 3+ GdNbO 4 Codoping of Li + Photoluminescence Sensitizer Rare earths

Impact of COVID-19-related lifestyle changes on diabetic macular edema

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 97-106页

作者： Bryce P.johnson Yu-Guang He Zachary M.Robertson Angeline wang Rafael L.Ufret-Vincenty Department of Ophthalmology UT Southwestern Medical CenterDallasTexas 75390-9057USA

AIM:To assess diabetic macular edema(DME)progression during the early phases of the COVID-19 pandemic,when severe societal restrictions raised the concern of possible deterioration of health in patients with systemic conditions,particularly those requiring frequent office ***:This is a multicenter retrospective chart review of 370 patients(724 eyes)with an established diagnosis of DME seen on 3 separate visits between January 2019 and July *** 1 was January 2019 to February 2020(considered pre-COVID-19),period 2 was March 2020 to December 2020(considered the height of the pandemic;highest level of pandemic-related clinical and societal regulations)and period 3 was January 2021 to July 2021(re-adjustment to the new“pandemic norms”).Main outcome measures included visual acuity,body mass index(BMI),blood pressure(BP),hemoglobin A1c(HbA1c),macular thickness,patient adherence to scheduled ophthalmology visits,and DME treatment(s)received at each *** facilitate measurement of macular thickness,each macula was divided into 9 Early Treatment Diabetic Retinopathy Study(ETDRS)-defined macular sectors as measured by OCT ***:There was no change of BMI,systolic BP,and diastolic BP between any of the time ***1c showed a very small increase from period 1(7.6%)to period 2(7.8%,P=0.015)and decreased back to 7.6%at period 3(P=0.12).Macular thickness decreased for 100%of macular *** central macular thickness decreased across all 3 periods from 329.5 to 316.6μm(P=0.0045).After analysis of multiple variables including HbA1c,BMI,adherence to scheduled appointments,different clinic centers,and treatment interventions,there was no easily identifiable subgroup of patients that experienced the increase in ***:DME doesn’t worsen during the COVID-19 pandemic,instead sustaining a very small but statistically significant *** identifying a mechanism behind our findings is beyond the scope of this study,potential explanat

关键词： COVID-19 diabetic macular edema diabetic retinopathy optical coherence tomography